Railway-track structure



Patented lune I3, I899.

F. r. STOCKWELL, In. RAILWAY TRACK STRUCTURE.

UNITED STATES PATENT OFFICE.

FREDERIC F. STOCKWELL, JR, OF SOMERVILLE, MASSACHUSETTS.

RAILWAY-TRACK STRUCTU RE.

SPECIFICATION forming part of Letters-Patent No. 626,734, dated June 13, 1899.

Application filed January 12, 1899. Serial No. 701,939. (No model.)

To all whom it may concern:

Be it known that I, FREDERIC F. STooK- WELL, Jr., a citizen of the United States, residing at Somerville, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvementsin-Railway=Track Structures; and I do hereby declare that the following is a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to that class of railwaytrack structures known as frogs, switches, crossings, and similar structures in which the rails comprising the tracks meet or converge or cross.

At the meeting-point of the rails in a frog or switch a point is formed which is narrower than the adjacent rails and is therefore subject to greater wear. The same is true of the floor or riser in a frog or crossing and is due to the narrow bearing-surface presented by the flange of the wheel in passing over the riser.

The object of my invention is to providea point and a riser which can be made of greater wear-resisting metal than the contiguous surfaces, such as hardened steel, and to provide a simple means for holding said points and risers in a body portion by means of the shrinkage of said body portion without detracting from the hardness of the said points or risers, and thereby produce a track structure which will wear uniformly throughout its whole bearing-surface, all of which I ac complish by means of the devices and construction herein shown and described.

In the drawings accompanying this specification, Figure 1 shows a perspective view of a frog embodying my invention and shows a plate cast in the top of said frog. Fig. 2 is a perspective view with the plate removed, showing the recess. Fig. 3 is a perspective view showing a plate having the points and the body portion.

lengths of the usual rails B B B B cast in its ends,and the method of castingin saidlengths of rails B B B B is to out openings in their webs, place them in the mold, and flow the cast-iron around them. The cast-iron fiows through the openings in the web and binds the whole fabric together; but I do not claim the above process, as that is shown in the patent to H. R. Luther, No. 483,964, dated October 4., 1892.

0 represents a plate, of steel or other metal having more shrinkage than cast-iron, which is somewhat smaller in length and breadth than the plate 0 The object of said difierI- ence in size will be explained more fully later on. The plate 0 is set in the mold, and the body portion A is cast about it. When the whole structure is cool, the said plate 0 can be easily driven out by a punch inserted through the holes D D, leaving the smooth walls 0 C C O of the recess 0 I find that by using the plate 0 instead of a sand core the recess O is always of a uniform dimension, and its walls 0 O C O are so smooth that it is not necessary to plane them to enable me to'obtain an accurate shrink fit of the plate C in the recess G I am also enabled to make the plate 0 in the form shown in the modification illustrated in Fig. 6, which modification affords a greater area exposed to the gripping force due to the shrinkage of Furthermore, it allows the points E to be made longer with onlya slight increase in the weight of the plate.

The plate 0 is provided with grooves in its upper side, which form the points E E and the floor or riser E. The short lengths of rails B B B B are provided with holes for attach ing the usual fish-plates.

The process of manufacturing my improved railwaytrack structure is as follows: The short sections of rails and the plate 0 are set in the mold and the cast-iron flowed around them. Provision is made for forming the holes -D D. After the whole structure has cooled the plate 0 can be driven out. Owing to the fact that the plate 0 is thin and made of metal having greater expanding properties than cast-iron, I find in practice that the large body of cast-iron heats the plate 0 sufficiently hot so that it has a temperature corresponding to that of the cast-iron before the said cast body portion has set so hard by cooling that it will not give. The plate and the body portion then cool together; but as the plate shrinks nearly double that of the body portion it will be found to be comparatively loose when the Whole structure is cool and can be easilydriven out by means of a punch inserted 3 in the holes D D.

The plate C is made slightly larger than the recess C and in order to insert saidplate C the body portion A is heated and expanded,

the plate 0* dropped into the recess C and, the body portion A allowed to cool and firmly hold said plate 0 by reason of its shrinkage.

Having described my invention, What I claim is 1. A process of manufacturing railwaytrack structures consisting of casting a body portion around rails and a plate having greater shrinkage than the metal of said body portion; removing said plate; and shrinking into the recess thereby left in said bodyportion a plate of high Wear-resisting properties having formed thereon points and risers.

2. As a new article of manufacture, a railcast body portion is expanded by low heat,

and firmly held therein by compression due to the contraction of the body portion after cooling to normal temperature.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, on this the 10th day of January, 1899.

FREDERIO F. STOCKWELL, JR.

' Witnesses:

' R. P. ELLIOTT,

WILLIAM L. DUCEY. 

